>>1727288>>1727234I guess I'm turning this thread into my own personal rant but it's worth it to help a fellow anon with a passion for submarines
If you're not looking to go very deep, an "ambient pressure" submarine is definitely the way to go. This basically works on the same principal as a glass turned upside down and pushed into water; the air bubble inside is trapped with nowhere to go. As you go deeper and the inside air volume shrinks from the water pressure, you blow compressed air into the cabin from scuba tanks to compensate.
This allows you a much wider range of material choices and shapes, and is extremely forgiving of mistakes in construction or imperfect seals. The disadvantage is that your body and everything in the cabin is exposed to a higher than sea level pressure (even though it's dry inside), so you still need to follow the tables you use for scuba diving
